/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */
package org.apache.iotdb.db.metadata.mtree.traverser.collector;

import org.apache.iotdb.commons.exception.MetadataException;
import org.apache.iotdb.commons.path.MeasurementPath;
import org.apache.iotdb.commons.path.PartialPath;
import org.apache.iotdb.db.metadata.mnode.IMNode;
import org.apache.iotdb.db.metadata.mnode.IMeasurementMNode;
import org.apache.iotdb.db.metadata.mtree.store.IMTreeStore;

// This class defines MeasurementMNode as target node and defines the measurement process framework.
public abstract class MeasurementCollector<T> extends CollectorTraverser<T> {

    public MeasurementCollector(IMNode startNode, PartialPath path, IMTreeStore store)
            throws MetadataException {
        super(startNode, path, store);
        shouldTraverseTemplate = true;
    }

    public MeasurementCollector(
            IMNode startNode, PartialPath path, IMTreeStore store, boolean shouldTraverseTemplate)
            throws MetadataException {
        super(startNode, path, store);
        this.shouldTraverseTemplate = shouldTraverseTemplate;
    }

    public MeasurementCollector(
            IMNode startNode, PartialPath path, IMTreeStore store, int limit, int offset)
            throws MetadataException {
        super(startNode, path, store, limit, offset);
        shouldTraverseTemplate = true;
    }

    @Override
    protected boolean processInternalMatchedMNode(IMNode node, int idx, int level)
            throws MetadataException {
        return false;
    }

    @Override
    protected boolean processFullMatchedMNode(IMNode node, int idx, int level)
            throws MetadataException {
        if (!node.isMeasurement()
                || (skipPreDeletedSchema && node.getAsMeasurementMNode().isPreDeleted())) {
            return false;
        }
        if (hasLimit) {
            curOffset += 1;
            if (curOffset < offset) {
                return true;
            }
        }
        collectMeasurement(node.getAsMeasurementMNode());
        if (hasLimit) {
            count += 1;
        }
        return true;
    }

    /**
     * collect the information of one measurement
     *
     * @param node MeasurementMNode holding the measurement schema
     */
    protected abstract void collectMeasurement(IMeasurementMNode node) throws MetadataException;

    /**
     * When traverse goes into a template, IMNode.getPartialPath may not work as nodes in template has
     * no parent on MTree. So this methods will construct a path from root to node in template using a
     * stack traverseContext.
     */
    protected MeasurementPath getCurrentMeasurementPathInTraverse(IMeasurementMNode currentNode) {
        IMNode par = traverseContext.peek();
        MeasurementPath retPath =
                new MeasurementPath(
                        new PartialPath(getCurrentPathNodes(currentNode)), currentNode.getSchema());
        retPath.setUnderAlignedEntity(par.getAsEntityMNode().isAligned());
        return retPath;
    }

    protected boolean isUnderAlignedEntity() {
        return traverseContext.peek().getAsEntityMNode().isAligned();
    }
}
